Hello @Marius Rochon , Thanks for using Microsoft Q&A Platform.
Try to make sure you have all the necessary permissions to use the resource, or the resource is not in a running state: https://learn.microsoft.com/en-us/azure/role-based-access-control/built-in-roles
To check the permissions, navigate to the Access control (IAM) tab of the resource (Azure portal) and verify the necessary roles assigned. May I know the resource region you are working on?
As per my understanding other possibilities are if the user has already selected the resource they want to work, then the Use resource button is disabled as it is not necessary to select the same resource again.
Please check if the current resource is already selected, then it is a default behavior.
I hope this helps.
Regards,
Vasavi
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